Behavioural response evoked by conspecific distress calls in two neotropical treefrogs. (15th October 2017)

• Record Type: Journal Article
• Authors: Forti, Lucas Rodriguez; Forti, Anna Bárbara Bella Sanches; Márquez, Rafael; Toledo, Luís Felipe
• Editors: Foster, S.
• Is Part Of: Ethology. Volume 123:Number 12(2017)
• Page Start: 942
• Page End: 948
• Publication Date: 2017-10-15
• Subjects: alarm signal -- animal communication -- anuran -- defensive strategy -- playback experiment -- predator–prey interactions; Animal behavior -- Periodicals; 591.5
• DOI: 10.1111/eth.12693
• Languages: English
• ISSNs: 0179-1613

Abstract

Abstract: Anurans emit distress calls when attacked by predators as a defensive mechanism. As distress calls may trigger antipredator behaviour even in individuals that are not under attack, we tested whether this defensive behaviour induced behavioural changes in neighbouring conspecifics. We compared the behavioural responses of two species of Neotropical hylid frogs (genus Boana ) to conspecific distress calls and white noise. Individuals of both species interrupted their vocal activity and decreased call rate after hearing the distress call. Natural variation on signal intensity calibrated among the nearest neighbours did not influence the response and we did not observe negative phonotaxis after any acoustic stimulus. Despite the fact that many predators are acoustically oriented, we could not determine if such response (reduced call rate) was induced by risk assessment or by the masking effect on advertisement calls. Boana faber responded similarly to white noise and distress calls, while B. bischoffi responded more intensely to distress calls. Duration of silence after playbacks in B. faber was longer than B. bischoffi . We suggest that, if the signals are interpreted as a risk cue by neighbouring conspecifics, each species may be preyed upon by different predators, as they may have led to distinct defensive strategies and different responses to distress calls. If risk assessment information is included in distress calls, it triggers behavioural responses only in the nearest neighbours, as we did not observe responses on the vocal activity of the interspecific chorus. Our results add relevant data about acoustic communication and interpretations by anurans, highlighting the importance of considering cues within common and widespread signals.